Yes, EPISODES is a Scrabble word!

Letter values in Scrabble US: E 1, P 3, I 1, S 1, O 1, D 2, E 1, S 1.

Is it a valid word?

EPISODES is a valid word in the official Scrabble dictionary (US), the UK Scrabble Dictionary and Words with Friends (ENABLE).

a happening that is distinctive in a series of related events
a brief section of a literary or dramatic work that forms part of a connected series
a part of a broadcast serial
film consisting of a succession of related shots that develop a given subject in a movie